Nanodiamonds might prevent tooth loss after root canals


People undergoing root canals may have gained a powerful, if tiny, new ally. Researchers from the UCLA School of Dentistry have published a new paper in the peer-reviewed journal ACS Nano showing that using nanodiamonds to fortify the material used in root canal treatments could significantly improve outcomes for patients.

Nanodiamonds are tiny particles formed as byproducts of diamond refining and mining. They are thousands of times smaller than the width of a human hair and are used in a range of medical applications- from cancer treatment to dentistry, imaging and regenerative medicine.

Each year, millions of root canal procedures are performed all over the world. A root canal is a treatment of the pulp of the tooth that is inflamed, infected, or dead. The dentists’ goal in all these procedures is to salvage the patients’ teeth from infected dental “pulp” — the part of the tooth that includes blood vessels and nerve tissue.

During a root canal, inflamed dental pulp is removed and the empty space is then filled in with a polymer called gutta percha, which is used in part because it does not react within the body. However it does have some shortcomings, including a limited capacity to fight or ward off infections leading to residual infections after root canals and subsequent tooth loss.

To overcome these issues, a team from  UCLA team developed and tested two types of reinforced gutta percha: One strengthened with nanodiamonds and another strengthened with nanodiamonds that had been pre-loaded with antibiotics.

A 3-D image of a tooth filled with nanodiamond-enhanced gutta percha, and an individual gutta percha point.

The co-authors who are UCLA Dentistry students, filled actual teeth from human patients. Using conventional radiography and micro-computed tomography, or micro-CT, they showed that the nanodiamond-enhanced gutta percha could be used to fill the tooth. They also noted that although the filler did not reach every space within the tooth, the rate of infection following the treatment was much lower when the preloaded nanodiamond was incorporated within the gutta-percha.

In the research’s second phase, the scientists tested nanodiamonds that had been loaded with amoxicillin, a broad-spectrum antibiotic used to combat infection. The rate of infection following the drug-reinforced nanodiamonds in the tooth effectively prevented bacteria growth.

“The nanodiamond-enhanced gutta percha combines many desirable properties into a single platform, including vastly improved mechanical characteristics and the ability to combat bacterial infection following a root canal,” said Dong-Keun Lee, a postdoctoral scholar in Ho’s lab.

During the next two years, the team plans to optimize the formulation of the nanodiamond-reinforced gutta percha and begin clinical trials at UCLA.

The original publication can be accessed here.